Question

I have a problem in that my class does not serialize, instead GWT RPC returns null every single time. I am trying to send objects of type Test through RPC. This is my class:

public class Test implements Serializable {
    /**
     * 
     */
    private static final long serialVersionUID = 2857617541722878389L;
    private int testID;
    private String testName;
    private String testTheme;
    private String subject;
    private int questAmount;
    private long created;
    private int timer;

    /**
     * @gwt.typeArgs <com.nimeria.client.TestCell>
     */
    private ArrayList<TestCell> tasks = new ArrayList<TestCell>();

    public Test(String testName) {
        super();
        this.testName = testName;
    }

    public Test(String testName, String testTheme) {
        super();
        this.testName = testName;
        this.testTheme = testTheme;
    }

    public Test(int testID, String testName, String testTheme, int questAmount,
            ArrayList<TestCell> tasks) {
        super();
        this.testID = testID;
        this.testName = testName;
        this.testTheme = testTheme;
        this.questAmount = questAmount;
        this.tasks = tasks;
    }

    public int getTimer() {
        return timer;
    }

    public void setTimer(int timer) {
        this.timer = timer;
    }

    public String getSubject() {
        return subject;
    }

    public void setSubject(String subject) {
        this.subject = subject;
    }

    public long getCreated() {
        return created;
    }

    public void setCreated(long created) {
        this.created = created;
    }

    public Test(int testID, String testName, String testTheme, String subject,
            int questAmount, long created, int timer) {
        this.created = created;
        this.testID = testID;
        this.testName = testName;
        this.testTheme = testTheme;
        this.questAmount = questAmount;
        this.timer = timer;
        this.subject = subject;
    }

    public Test() {
        // TODO Auto-generated constructor stub
    }

    public int getTestID() {
        return testID;
    }

    public void setTestID(int testID) {
        this.testID = testID;
    }

    public String getTestName() {
        return testName;
    }

    public void setTestName(String testName) {
        this.testName = testName;
    }

    public int getQuestAmount() {
        return questAmount;
    }

    public void setQuestAmount(int questAmount) {
        this.questAmount = questAmount;
    }

    /**
     * @gwt.typeArgs <com.nimeria.client.TestCell>
     */
    public ArrayList<TestCell> getTasks() {
        return tasks;
    }

    /**
     * @gwt.typeArgs tasks <com.nimeria.client.TestCell>
     */
    public void setTasks(ArrayList<TestCell> tasks) {
        this.tasks = tasks;
    }

    public String getTestTheme() {
        return testTheme;
    }

    public void amountIncrement() {
        this.questAmount++;
    }
}

public class TestCell implements Serializable {

    /**
     * 
     */
    private static final long serialVersionUID = 985354326237784028L;
    private int taskId;
    private String quest;
    private int qustionsAmount;
    private int rightAnswer;
    private int type;
    /**
     * @gwt.typeArgs <java.lang.String>
     */
    private ArrayList<String> qustions = new ArrayList<String>();

    public TestCell(int taskId, int qustionsAmount, int rightAnswer, int type) {
        super();
        this.taskId = taskId;
        this.qustionsAmount = qustionsAmount;
        this.rightAnswer = rightAnswer;
        this.type = type;
    }

    public TestCell(int taskId, int qustionsAmount, int type) {
        super();
        this.taskId = taskId;
        this.qustionsAmount = qustionsAmount;
        this.type = type;
    }

    public TestCell(int taskId, int qustionsAmount) {
        super();
        this.taskId = taskId;
        this.qustionsAmount = qustionsAmount;
    }

    public TestCell(int taskId, String quest, int qustionsAmount,
            int rightAnswer, int type, String q1, String q2, String q3,
            String q4, String q5) {
        this.taskId = taskId;
        this.quest = quest;
        this.qustionsAmount = qustionsAmount;
        this.rightAnswer = rightAnswer;
        this.type = type;
        this.qustions.add(q1);
        this.qustions.add(q2);
        this.qustions.add(q3);
        this.qustions.add(q4);
        this.qustions.add(q5);
    }

    public int getType() {
        return type;
    }

    public void setType(int type) {
        this.type = type;
    }

    public int getTaskId() {
        return taskId;
    }

    public void setTaskId(int taskId) {
        this.taskId = taskId;
    }

    public String getQuest() {
        return quest;
    }

    public void setQuest(String quest) {
        this.quest = quest;
    }

    public int getQustionsAmount() {
        return qustionsAmount;
    }

    public void setQustionsAmount(int qustionsAmount) {
        this.qustionsAmount = qustionsAmount;
    }

    public int getQustionNumber() {
        return taskId;
    }

    public void setQustionNumber(int qustionNumber) {
        this.taskId = qustionNumber;
    }

    public int getRightAnswer() {
        return rightAnswer;
    }

    public void setRightAnswer(int rightAnswer) {
        this.rightAnswer = rightAnswer;
    }

    /**
     * @gwt.typeArgs <java.lang.String>
     */
    public ArrayList<String> getQustions() {
        return qustions;
    }

    /**
     * @gwt.typeArgs questions <java.lang.String>
     */
    public void setQustions(ArrayList<String> qustions) {
        this.qustions = qustions;
    }
}

And this is my RPC call:

conectModule.saveTest(t, new AsyncCallback<Integer>(){
    public void onFailure(Throwable caught) {
        Window.alert(caught.getMessage());
        Window.alert(caught.getLocalizedMessage());
    }

    public void onSuccess(Integer result) {
        Window.alert("Тест сохранен"+result);

        try {
            loadTestListing();
        } catch (Exception e) {
            e.printStackTrace();
        } 
    }
});

Answer 1

Serializable classes must have a default (zero argument) constructor, i.e. Test() and TextCell().